Fix non-determinism in selecting between equal-length names which refer

to the same declaration when correcting typos. This is done by
essentially sorting the corrections as they're added.

Original patch by Kaelyn Uhrain, but modified for style and correctness
by accounting for more than just the textual spelling.

This still is a bit of a WIP hack to make this deterministic. Kaelyn
(and myself) are working on a more principled solution going forward.

llvm-svn: 134038